August 31, 2013

Discovery Of ‘Molecular Brakes’ Could Lead To Possible Cure For Jet Lag

by editor

redOrbit Staff & Wire Reports – Your Universe Online

Researchers have reportedly located a biological trigger for jet lag -- a discovery that could lead to the development of new drugs designed to help people recover more quickly from travel into new time zones.

Writing in the August 29 edition of the journal Cell, the study’s authors explain they have pinpointed a protein known as SIK1, which apparently plays a key role in preventing the body’s internal circadian clock from adjusting too quickly to changes in the environment.

That internal circadian clock helps people and most other creatures synchronize their bodily functions to the 24-hour cycle of light and dark in any given day, the researchers explain. However, the clock can be disrupted by travel into different time zones, or even by working a different shift than normal.

“Furthermore, it can take up to a day for the body to adjust to each hour that the clock is shifted, resulting in several days of fatigue, indigestion, poorer cognitive performance and sleep disturbance,” they explained in a statement. The team set out to identify the biological mechanisms responsible for that slow adjustment period.

Senior research scientist Dr. Stuart Peirson of the Oxford University Nuffield Department of Clinical Neurosciences and colleagues from the University of Notre Dame, Washington University in St. Louis, Oxford University and F. Hoffman La Roche, analyzed about 100 genes that begin working when they are exposed to light -- thus beginning the process of retuning the circadian clock, according to USA Today.

However, explains BBC News health and science reporter James Gallagher, they found as the genes were activated, they were turned off again by the SIK1. Essentially, the researchers said, the protein was acting like “molecular brakes” by limiting the effect of light on the internal clock. They found “uncoupling” these so-called brakes in mice (reducing the function of SIK1) allowed the rodents to quickly adapt their body clocks when they were effectively shifted six hours.

“We reduced levels by 50-60 percent, which is big enough to get a very, very big effect. What we saw was the mice would actually advance their clock six hours within a day [rather than taking six days for untreated mice],” corresponding author Russell Foster, Oxford University Sleep and Circadian Neuroscience Institute, told Gallagher. “We've know there's been a brake on the clock for some time, but we had absolutely no idea what it is, this provides a molecular basis for jet lag and as a result new targets for potentially developing new drugs.”

In fact, Dr. Peirson told the Daily Mail the mice recovered from jet lag approximately three times more quickly, and in some cases did not experience the phenomenon at all. Foster added the scientists were still “several years away” from a potential jet lag cure, but added “understanding the mechanisms that generate and regulate our circadian clock gives us targets to develop drugs to help bring our bodies in tune with the solar cycle. Such drugs could potentially have broader therapeutic value for people with mental health issues.”